In general, examples of a solid-state image pickup device include a solid-state image pickup device configured such that a photoelectric conversion unit and a peripheral circuit unit which are disposed on different substrates are electrically connected to each other using micro bumps. PTL 1 discloses a peripheral circuit unit which is used to read a signal from a photoelectric conversion unit such as a vertical scanning unit and a horizontal scanning unit and which is disposed on a second semiconductor substrate which is different from a first semiconductor substrate on which the photoelectric conversion unit is disposed.
Specifically, on the first semiconductor substrate, the photoelectric conversion unit, a floating diffusion (FD), a transfer transistor which transmits charge of the photoelectric conversion unit to the FD, and a reset transistor are disposed.